Endocrine Flashcards
Allow cells to communicate with each other to regulate body cavities
Chemical messengers
Controlled release of chemicals from a cell
Secretion
Four classes of chemical messengers
Autocrine
Paracrine
Neurotransmitters
Endocrine
Stimulates the cells that originally secreted it
Autocrine
Example of autocrine chemical messengers
White blood cells
Local messengers secreted by one cell type
Paracrine
Example of paracrine
Histamine
Secreted by neurons to activate another neuron
Neurotransmitters
Example of neurotransmitters
Acetylcholine
It is secreted into synaptic cleft
Neurotransmitters
Secreted into blood stream by certain glands and cell
Endocrine
Example of endocrine
Epinephrine
Includes glands and specialized endocrine cells that secreted hormones in the blood stream
Endocrine system
A chemical messenger that is secreted into the blood
Hormones
The study of endocrine system
Endocrinology
Have ducts that carry their secretions to the outside of the body
Exocrine glands
Regulate almost every physiological process in our body
Hormones
Specific sites where hormones produce a particular response
Target site / effectors
Two chemical nature
Lipid soluble hormones
Water soluble hormones
Non-polar; include steroid hormones, thyroidnhormones, and fatty acid hormones
Lipid soluble hormones
Polar; includes protein,peptide, and amino acids
Water soluble hormones
Rapid degration of enzymes
Proteases
Rapidly degraded by enzymes
Water-soluble hormones
Types of stimuli regulating hormones
Humoral Stimuli
Neural Stimuli
Hormonal Stimuli
Directly blood-borne chemicals to hormones
Humoral stimuli
Directly by blood borne chemicals
Humoral stimuli
Stimulated by action potential, releasing neurotransmitter
Neural stimuli
Hormone is secreted to stimulate the secretion of ofher hormones
Hormonal stimuli
Chemical messengers secreted by neurons directly to blood
Neuropeptide
‘Specialized neuropeptides’ that stimulate hormone secretion
Releasing hormones
Prevents further hormone secretion once a set point is achieved
Negative feedback
Self promoting system whereby the stimulation of hormone secretion increases by time
Positive feedback
Proteins where the hormones bind
Receptors
The location on cell where the hormones bind
Receptor Site
Tendency for each type of hormone to bind to one type of receptor
Specificity
Often found in cell nucleus where lipid soluble hormones bind
Nuclear receptors
2 classes of receptors
Nuclear receptor
Membrane-bound receptor
Proteins that extend across the cell membrane where water solubles bind
Membrane-bound receptors
Forms from combination of hormones and its receptor
Transcription factor
Fingerlike projections that recognize and specific nucleotide sequence in dna
Hormone-response elements
Another word for pituitary gland
Hypophysis
Small gland that about the size of pea
Pituitary gland / hypophysis
Small gland that rests in sella turcica which is controlled by hypothalamus
Pituitary gland
Pituitary gland is controlled by
Hypothalamus
Secretes hormones that influence growth, kidney function, birth, milk production
Pituitary gland / hypophysis
Endocrine control center of the brain
Hypothalamusb/ hypophysis
A stalk that connects pituitary gland and the hypothalamus
Infundibulum
Made of epihelial cells from embryonic oral cavity
Anterior pituitary
Extension of brain and composed of nerve cells
Posterior pituitary
Capillary beds and veins that transport the releasing and inhibiting hormones
Hypothalamic-pituitary portal system
